Automatic telegraph system



June 9, 1925.

' G. A. LOCKE AUTOMATIC TELEGRAPH SYSTEM 5 Sheets-Sheet 2 Filed NOV. 23, 1922.

//7 en/0r. Georg AL'oc/re y ,7

June 9, 1925. 1,541,229

' G. A. LOCKE AUTOMATIC TELEGRAPH SYSTEM I Filed'iNov. 23-, 1922 5-She ets-'Shee't 5 Patented June 9,1925.

UNITEDE STAT Es PA NT OFFICE.

GEORGE A. ocKE, or GLEN oovE,'1vEw YORK, ASSIGNOR T0 WESTERN n'IjEorRIc celerany, mcoRPoRATnn'oF. NEW YORK, 1v. Y., A CORPORATION or N W YORK.

AUTOli/[ATIC TELEGRAPH SYSTEM.

iYpplicat'ffi f led November W922. Serial No. 602,724.

To all whom it may co ce n;

Be it known that I, GEORGE A. Looms, a citizen of the United States, residing at Glen Cove, in the county of Nassau, State of New York, have invented certain new and useful Improvements in Automatic Telegraph Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to automatic telegraph systems. An object of the'invention is a synchronous multiplex system wherein a plurality of repeater stations are associated with a single line conductor;

Theinvention, according to its preferred form, provides a synchronous multiplex telegraph system extending between two remote points and having a plurality of intermediate repeater stations which act as the corrected stations, while either of the termi nal stations may funwimn as a pace setting station. In addition thereto any of the re .peater stations may act as. the pace setting station, in which case the other'stations function as the corrected stations.

A- better understanding of the invention may be had from the following description taken in conjunction with the accompanying drawings wherein one embodiment of the invention is disclosed.

Fig. 1 represents a telegraph system with two terminal stations arranged for communication through two repeater stations. Fig. 2 is an amplification of Fig. 1 and shows diagrammatically a telegraph system of the iharacterillustrated in Fig. 1, and also represents the manner of dropping off channels at the repeater stations. Fig. 3 shows the apparatus necessary at the termi nal stations. Figs. 4, 5 and 6 represent when Fig. 4 is on the left with Fig. 5 on the right thereof and Fig. 6 on the right of Fig. 5. the equipment located at each of the repeater stations. It is understood, of course,

' that as many repeater stations may be employed-as are necessary for the transmission of signaling impulses between the respective stations without appreciable distortion. Fig. 7 represents a mechanical structure for shifting or orientating the brush arms of the multiplex distributors at each of the several stations, the repeater stations as well as the terminal stations.

Referring to Fig. 1, the full lines indicate the number of channels in one direction and the broken lines the number of channels in the opposite direction, with arrows indicating the termination of the respertive channels. In Fig. 2, which is diagrammatic of the apparatus for giving the number of channels indicated in Fig. l, the small circles indicate the transmitting and receiving mechanisms at the respective stations. For

the sake of illustration, the terminal stations, Figs. 1 and 2, are designated as New York and San Francisco, with the repeater stations located at St. Louis and Denver. lVith reference to the system shown diagrammatically in Figs. 1 and 2, it is to be understood that the terminal stations and repeater stations associated therewith operate in synchronism. It is. understood also that the multiplex arms at the terminal and repeater stations may be extended by means of startsstop equipment to distant or outlying stations, as shown in 'Patent- No. 1,407,042,issued February 21, 1922,- to P. M.

Rainey. As suchequipment does not form a part'of the present invention, a description thereof is thought unnecessary.

In Fig. 2 there is shown diagrammatically a full quadruple duplex system with someof the multiplex arms dropped off. at the repeater stations. At the. New York station, for example, there are illustrated four transmitters T and four receivers R arranged to be connected by means of multiplex distributors SD and RD, respectively, with the line circuit 8 connecting New York with St. Louis, the first repeater station. At eachv of the repeater stations St. Louis and Denver there are illustrated two receiving distributors and two sending distributors of the multiplex type, with two transmitters T and two receivers R associated with the respective distributors. San Francisco four transmitters T and four receivers R associated with transmitting distributors SD and receiving distributors RD, respectively, are illustrated.

The equlpment and necessary circuits for cisco terminates ateach of the stations in line relays. As shown in Fig. 3, the sending and receiving distributor faces are here shown developed, the sending distributor faces SD each comprising a continuous ring and a segmented ring 16. In the arrange ment illustrated, each 16 consists twenty segments,each of which is insulated from all of the other segments and adapted to connected to its respective continuous rin 15 at regular recurring intervals by continuously rotated distributor brush 1?. The local continuous ring 18 is shown connected to ground and thelocal segments 19 are adapted to be connected sequentially to the groundring by means of a distributor brush let for controlling operations in the local transmitting instruments. The receiving distributor RD, like'the sending distributor SD, comprises a continuous ring 20 and a segmented ring 21 comprising a corresponding number of insulated segments. The receiving segments 21 are also adapted to be connected sequentially to the continuous ring 20 by means of a continuously rotating distributor brush '22; Also associated with continuous ring 20 and-segmented ring 21 are continuous ring 26 and segmented ring 27, the latter of which are adapted to be connected by means of a distributor brush 28, for controlling local operations in the receiving printers. For example, the local distributor segments may be employed to control the printing magnets in the receiving printers. As shown in Fig. 3, the receiving segments 21 are illustrated as being of a shorter length than the sending segments, which is customary inactual practice in order that only the central or undistorted portion of each signaling impulse will be received and distributed either to selecting magnets of receiving printers ll or storing relays in case it is desired to repeat the impulses to'a system of the start-stop type;

-ln connection with Fig. 3, there isshown apparatus and circuits for providing a sys-. tem of communication between the different stations whereby four messages may be transmitted over the connecting circuit in each direction. There is also illustrated in Fig. 3 a' group or bank of lamps L includ each pair of magnets is adapted to be encrgized alternately over circuits controlled by a driving fork 32. The synchronous motor or phonic wheel 30, which may be of any well known type, is arranged to be driven of-an operating magnetifil) until the circuit of magnet 39 is permanently open. The starting distributor shown in Fig. 7 comprises a continuous ring 33' and a segmented ring 34. The alternate segments of the segmented ring 34 are strapped together, and in turn connected through the contacts of key 39 to alternate pairs of the driving magnets 31 -0f the phonic wheel motor 30. The continuous ring 33 is connected to battery and ground and is adapted to be connected to the segments of the ring 34 by means of a distributor brush This brush 35 always rests on one'of the segments of the ring 34:. VI hen the key is actuated so as to close itslower contacts, current will-flow from the battery connectedto the ring 33, brush and the segment of the segmented ring 3% upon which the brush is resting, and a pair of diametri cally opposite magnets 31. Thus, the motor -may be started automatically from an initial state of rest and brought up to the desired speed. Current through the other set'of magnets will cause the 'motor 3.0 to start rotating and will thus move the brush 35 which is secured to the armature of the motor to-move from one segment to another, thereby connecting the sets or pairs of. magnets 31 alternately in circuit with the battery connected to the continuous ring 33. Theflmotor 30 will increase in speed until the desired speed is attained, and then ing a specially designated lamp 25. These lamps. are adapted to be connected by means .of keys 23 with the'receiving-segments 21:

The keys 23 thereby serve to connect the selecting magnets of the printer ll with the receiving segments, as well asconnecting these segments with the indicating lamps 11. This feature of the system is disclosed and claimed in Patent No. 1,388,507, issued August 23, 1921. i

In connection with Figs; 4,5 and 6, there is shown a well known phonic wheel motor 30 of the La Cour type, driven by stationary electromagnets 31. arranged in pairs, and

the key 35 is moved to close its upper. contacts or the position shown in thedrawing.

The actuation of the key 35 in'this manner disconnects the segmentsof the ring 34: from the magnets 31 and places these magnets under the control of the tuningfork 32. For the purpose of indicating whema condition of; synch'ronism exists between the motor 30 and the electrically driven-tuning fork 32, an indicating lamp 36 is provided.

hen the motor 30,. while being driven by current supplied from battery to the continuous ring 33, reaches a speed approximating the speed of the driving fork 32, the lamp. 36 will appear. lighted continuously or for a considerable period of time, or else will be extinguished for a like period of time, depending upon the group of alternate segments of the ring 34, upon which brush is resting when the lower prong of the driving fork 32 makes engagement with contact 37, that is, if the brush 35 is traveling over the segments connected to the key contact to which thelamp 36 is connected. Each time the lower prong of the tuning fork 32 makes contact with contact 37, a

circuit extending from the negative pole of battery 38 is completed. If, on the other hand, the brush 35 is passing over segments not. connected to the contact to which the lamp 36 is connected, each time the prong of the fork engages contact 37, then the cir-' cuit through the lamp 36 will be opencon tinuously and the lamp accordingly will not be lighted. When this condition exists, thereby indicating a condition of synchronism, the key-35 is actuated such as. to close its upper contacts, thereby lacing the motor 30 under the control 0 the tuning fork 32. This method of starting the distributor motor automatically from an initial state of rest iscovered by a copending application, Serial No. 409,132, filed September 9, 1920.

Likewise'in the upper left-hand corner of Fig. 3, there isshown a self starting arrangement for La Cour motors which is identical to that just described and which will therefore not be described again.

The circuit of the operating magnet 39 is normally from grounded battery 38, fork 32, contact 40, winding of operating magnet 39, through resistance 41, to ground. The rate of vibration of the fork 32 may be varied by closing key 42, which permanently sh0rtcircuits resistance 41, or the resistance 41 may be automatically and iiitermittently short-circuited as The operation of i'elay44 is controlled by the line impulses through the correcting distributor comprising a continuous ring 45 r and a segmented ring 46, the segments of i the segmented ring being adapted to be con-' nected with the continuous ring by means of a distributor brush 47. .Bearing in mind that the speed. of the distributors at the terniinal stations as well as those at the re peater stations shown in the respective fig-.

ures is controlled by or corrected from the pace setting station, and assuming that the distributor brushes travel slightly'faster or slower than the brushes of the pace setting station, then it is necessary to slow down or increase the speed of the terminal and re: peater distributors automatically and at rapidly recurring intervals. *This in the present invention is accomplished by varying the resistance in the circuit of the operating magnet 39 through the instrumentality of relays 48, 49 and 44. It will be noted that when key 80, which is designated as the correcting key, is thrown to the left, thereby closing contacts 81 and 82, the windings of the relay 48 are connected to the armature of line relay 12. Thus, whenever desired .through contacts 43 controlled by relay 44.

the line relay 12 makes engagement. with one or the other of its contacts, current will "flow from the grounded battery controlled by the armature of this relay, through one winding of relay 48, which responds to such current for causing the correspondingoperation of relay 49. Relay 49 accordingly applies to the continuous ring 45 battery connection, which is subsequently connected with the windings of relay 44 upon the passage of the brush 47 over the segment to which the windings of'this relay 44 are current flows through the lower winding of relay Patent No. 1,279,905, issued September 24,

1918. Further discussion thereof is considered unnecessary. I y

In Figs. 4, -5 and Gthere is shewn the necessary apparatus and circuit. arrangements required at each of the repeater stations by repeating two channels from each peater station, or in the case of the last repeater station, to the other terminal station. In Fig. 4 there is shown a pair of sending distributor ringsSD and a pair of receiving distributor rings RD associated with each line circuit.

sending and receiving rings there is illustrated in connection with each distributor unit a pair of local segmented rings 60 and 61. Segmented ring 60 is shown connected to battery and the segmented ring-61 is adapted to be connected sequentially-to the ring 60 by means of a distributor brush 62 for controlling operations in the local re-x ceiving and transmitting instruments. For example, the local distributor segments may be utilized to control the operation of printing magnets in the receiving printers and the operation of stepping or tape feeding l magnets of automatic tape transmitters.

Referring to Fig. 4, the first two groups of five segments of the transmitting distrib-' i'itor are shown connected directly to contacts of local transmitters T, while the third and the fourth groups of five segments are arranged for the purpose of distributing impulses to the adjacent line sections. Likewise, the first and second groups of'five receiving segments are connected with 'receiving printers R. The third and fourth terminal station through to the other rev i In addition to the I groups ct five receiving segments are connected with storing relays 63 and 54, whereby impulses received on the third and itourth groups of receiving segments will be stored and retransmitted throughthe corresponding sections of the sending distributor SD associated with the line conductor 11 extending to the repeater station designated as Denver.

In 5 there is shown the equipment 'and circuits necessary for the reception and transmission of impulses from the linell t the line 8 connecting Denver and St.

Louis, and St. Louis and NewYork. There is shown in this figure a scnd1ng.d1str1butor SD and a receiving distributor RD in addition to a pair of segmented rings 70 and 71. Like in the previous case, the segmented ring 70 is connected with a source of battery and is adapted to be connected with the segmented ring 71 by means of a distributor brush 72. ,The local segments may be used for performing the local operations,-

such as the operation ot'the printing magautomatic transmitters T.

net of the receiving printers R and the receiving distributor RD are shown con-.

nected with receiving printers R. Likewise, the third and fourth groups of five segments of the receiving distributor RD are connected with storing relays 73. and 7a,

8, which will be which are adapted to be energized alternately upon the passage of the brush associatedwith the distributor RD over the particular segments to, which these relays are connected. The armatures of these relays are' connected to alternate segments of the segmented ring of the sending distributor SDso that upon the passage of the brush associated with this distributor over the particular segments, impulses in accordance with those received from the linesection 11 will be repeated into the line section free from bias and distortion.

There is also associated with the receiving distributor RD and the sending distributor SD group or series of indicating lamps L, which serve a purpose identical to that previously described in connection with Fig. 3. These lamps are arranged to be connected in circuit by a switch having a plurality of contacts with the receiv-j ing segments of the receiving 'distributor As shown in this figure, the contacts of the switch 65 serve either to connect the run lyii ll om the repeating station to the windings of the storing relays 63 and 64:.

ing distributor repeater unit are phasing keys 67 and '77 for operating a plurality of contacts. while tliere is shown common to the reccming and sending distributors at each of the repeater stations a. correcting key 80, which likewise controls a plurality of contacts. From reference to Fig. 2 it will be-noted that the distributors, storing relays, switching means, etc., associated with the line circuit are replicas of those associated with each of the other line circuits. Consequently, a description of one unit will sutfioe for all.

The repeater stations, as illustrated in Figs. 4: and 5, are arranged for repeating signals received'o'ver each of .the line cir cuits out of each oi the other line circuits. For example, in the arrangement shown, a selecting impulse received from theline circuit. 8 will cause the operation of relay -76, and either positive or negative battery,

depending upon. the position of this, relay,

will be connected to the co-ntinuous"ring 81 of the receiving distributor RD, brush 82,

segment 83 oft-he segmented rlng of, this distributor, to storing relays 73 Git 74:, de-

pending upon thebharaten of the signaling impulse and the positionpf the brush 82 upon receipt of each signaling impulse.

The relays 7 3 and 74 upon being energized will actuate their armatures to connect positiveor negative battery through the sending segments of the sending distributor SD, whereupon the sending brush of this distributo-r in passing over the corresponding.

segments will transmit 'over the line'circuit 8 corresponding impulses. In order"that the signals from each terminal station may be properly repeated at the repeater station and distributed to the proper line circuits, it isne'cessary that the sending and receiving brushes at the terminal and re peater stations bearthe proper phase relation with respect tonne another, and the' distributors all stations operated in synchronism.

At each of the terminal multiplex stations as well as at the several repeater stations there are provided "multiplex distrib utors of'the character shown, in Fig.

Each of these distributors comprises a mi1ltiplex distributor face 9.0and a pair of ro tatable distributor faces 91 and 92} Arranged in operative relation to each of the for driving the rotatable members. On the motor shaft there is mounted a fly wheel 97 of 'a well known type. The distributor brushes 94 and-95 are driven through beveled gears 98 and 99 cooperating with a beveled gear 100, the'brush arm 93 being rigidly secured to the motor shaft. Each of the gears 100 is provided with a handle 101, which may be connected with each other by means of a. bar 102 for locking the two distributor brushes 94 and 95 together. Thus, when one is rotated, the other will be rotated through a corresponding distance. A distributor of the character shown in Fig. 7 is disclosed more fully and claimed in a copending application, Serial No. 420,908, filed November 1, 1920.

For the successful operation of the system disclosed in the respective figures, it is necessary that the time lags in the separate lines from the terminal stations to the repeater stations and that between the respec tive repeater stations are compensated for separately at the different stations. In other words, the speed and phase of the respective distributors at each of the stations is adjusted so that the outgoing signals arrive: at the respective stations at the proper instant when the'distributor brushes are passing over the corresponding segments, thus preventing overlapping of the messages or reducing the operating margins,.t at is, two or more different messages originating in different channels may be combined at the repeater station and sent out in their proper consecutive order over the proper channels without interference. This necessitates the provision of distributors at the respective stations, designed so that both the sending and receiving rings (or the brushes) may be orientated independently of each other. It is understood, of course, that the distributors at therepeater stations are likewise capable of orientation as it is necessary that such be the case in order to take care of phase finding.

The receiving brushes at each of the several stations are brought into correct relation by means of phasing keys, such as those shown in Figs. 3, 4 and 5, similar keys being employed at the other stations (not shown) The phasing keys take care of this by grouping the sending segments of each of the distributors so that a marking impulse is sent out over each line from one of the segments, and. spacing impulses sent out from the other nineteen segments. The multiplex receiving brushes at each of the stations are then adjusted until the correct character is recorded by the printer R, which corresponds to the position of the particular segment chosen to send out the marking impulse. If lamps are used, as illustrated by L in Figs. 3, 4 and 5, the receiving brushes of the terminal distributor will be rotated until lamp, No. 25 or the specially designated lamp flashes. Then the phasing keys at the correctly aligned station are thrown-so that the sending segments of the distributor, the receiving face of which has been orientated, are connected as previously described. This operation is continued until the severaldistributors are orientated so that the proper lamp of the series of lamps L flashes, indicating the correct alignment of the distributors. The operation of the system whereby the distributors at the several stations are brought into the proper phase relation is as follows: The lamp keys 23,65 and at the terminal station-New York and repeater sta tion St. Louis, as well as the corresponding keys at the repeater station Denver and the terminal station San Francisco, are thrown to the position whereby the lamps Lindividual thereto are connected with the receiving segments of the distributor RD. Assume also that the distributors have been. started in a manner similar to that described in connection with Fig. 6. The phasing key 87 at the terminal station New York is then thrown so that segment No.' 1 of the sending distributor is connected with negative battery, while the remaining nineteen segments are connected with positive battery. As the brush 17 passes over the respective segments, impulses in accordance with the setting of the phasing key 87 are transmitted over the line 8 to the repeater station St. Louis, where theyv are received on the linerelay 9'. Relay 9 responds to such impulses and repeats to pole changing relay 76 through the contacts of keys 79 and 80 to the continuous ring 81 of the receiving distributor RD. The impulses are then impressed on the series of lamps L upon the passage of the brush 82 over .the corresponding segments.

In order to adjust the receiving face RD so that the impulse is recorded properly on d the series of lamps L, that is, the lamp designated by the numeral -25 flashes the speed of segment is connected with negative battery,

while the remaining nineteen segments are connected with positive battery. Likewise, the brush of the sending distributor SD transmits over the line 11 to the repeater station at- Denver impulses in accordance with the setting of the phasing key 77. The attendant at the repeater. stationv Denver then adjusts the speed of the driving motor at this station, and orientates the receiving ring or brush of the receiving brush RD so that lamp No. 25 flashes upon the passage of the brush over the corresponding segment.

-When the receiving distributor is brought into correct phase relation with the sending distributors at the terminal station New York and the repeater station St. Louis, the phasing lmy at the repeater station Denver is thrown to set up a condition similar to that described in connection with the operationof phasing keys 87 and 77 at the sta= tions New York and StLouis, respectively. Correspondingly, the receiving distributor RD at the terminai station San Francisco is adjusted, or rather orientated, until the proper lamp or the lamp designated by the No. flashes to indicate the proper phase adjustment; In order that the several distributors will be in proper plia'se'relation, it is necessary that'corresponding impulses be repeated back through the several re peater stations to the terminal station New York in order thatsuch station can adjust its receiving distributor face tocompensate for line lag. The phasing key at. San Franterminal'station San Francisco. The phascisco is thereupon thrown to connect nega- 25.

tive battery with. segment No, l of the sending distributor and positive battery with the remaining nineteen segments of this distributor. Like the previous case, the receiving distributor RD for receiving from the west is adjusted sothat its phase relation is identical to the sending distributor at the ing key east at the repeater station Denver is then thrown for producing a condition similar to that described in connection with the throwing of the phasing key at the terminal station San Francisco; Likewise, the receiving distributor RD for r'eceivingfrom the line 11 the. phasing impulses transmitted from the repeater station Denver, is orientated until'the proper lamp flashes. Then .the phasing'key east is thrown for causing the impression on the line 8 from the repeater stationvSt. Louis impulses in accord ance with those determined by the opera- 1 tion of the phasing key east. The terminal I ing stations, are restored to normal.

station New York then adjusts the receiving distributor RD so that the proper lamp 25 Hashes, indicatingthat the several distributors are iii-the proper phase relation. Following the operation first described, all keys at the several stations except the .correcting key at the terminal station New York, which for the purpose of illustration has .been selected asthe pace setting station, the other stations, such as St. Louis, Denver and San Francisco, being designated as the correct- Inasmuch as' the terminal station New York is to, serve as thepace setting station, keys 80 at the respective repeater station are thrown so; that the correcting circuit;

extending to relay 48'is under the-control of line relay 9. It is thus seen that for each reversal. of current over the line 8, relay 48 will respond for causing the energizationof relay 49, and consequently the energization of correcting .relay 4% upon the passage of the brush 47 over the segmented ring 46, as

welh'as-controlling the short-circuiting' of the governingresistance ll.

A better understanding ofthe system can perhaps be obtained from a description of the operatioirwhich takes place in the transmission of a. message. Let it be assumed as a matterof illustration that a message is to be transmitted from New Yor; to San Francisco. Also let it be assumed that mes} sagesare being transm tted between New York and St. Louis, New York and Denver,

St. Louis and Denver, St, Louis and San Francisco, and Denver and SanzFrancisco in accordance with the: diagrammatic show} ing of Fig. 1. Ttwill be assumed also that the'cliaracter D, which according tothe five unit or Baudot code is represented byfive units, of negative current, positive current, negative current, negative current and positive current, is to be transmitted. The transmitter T at New York is accordingly set up. -The contacts of the transmitter. T at the terminal station New Yorltgare accordin'gly-operated for producing the condition characteristic of thecharacter D. For

the particular selection chosen, contacts 55 and "5870f the transmitter T will be closed,

'While the remaining contacts will be open. :As the distributor brush 87 passes over segments to which the contacts 55 to 59, inclusive, are connected, impulses inaccordance with those determined by the setting of these contacts will be impressed on the apexiof the ratio arms in which receiving relay 68 is connected. It is understood, of course, that receiving 1'elay: 68, as is true of systems provided for duplex operation, responds only to incoming impulses, it being non-responsive to outgoing impulses. Ac-

cordingly, relay. 68 does not respond to the impulses transmitted upon the passage of thebrush 17 over the segments' towhich the contacts 55-to. 59, inclusive, areconnected. The impulses passing oveigthe line conductor 8 are received at 'St. Louis on line r'elay 9. This relay responds to such impulses and impresses through the contacts of key on relay 7 6, impulses in accordance with those determinedby the s'etting ot the contacts 55 to 59, inclusive, of the transmitter T. Inasmuch as the brush arms at the respective distributors are rotating in synchronism, the distributor brush82 of the receiving distributor RD at St. Louis will be passing over the segments of the fourth-group at the same time'the sending distributor at the terminal station New York is passing over the corresponding segments. brush 82 passes over. the segments of the fourth group, storing relays 7 3 and 7e will" be energized alternately for storingthe im- As the I pulses in accordance with those received from the line connecting New York and St.

Louis. Accordingly, as the brush 85of the sending distributor SD passes over the segments of the fourth group, the arinatures of the storing relays 73 and-74 being connected to alternate ones of the segments thereof, impulses in accordance with those stored in the relays 73 and 74 will be 'impressed on the apex of the ratio arms in which receiving relay 12 is connected, and thence over the line 11 tothe repeater station Denver. The im ulses then being received at Denver cause tie operation of apparatus similar to that described for the repeater station St. Louis, and since it would be but a matter of reiterating the description pertaining tothe apparatus at St. Louis, further description thereof is considered unnecessary except to statethat the impulses corresponding with those transmitted over the line 8, and accordingly over line 11, will be repeated into the line 13. The impulses will be impressed on a. line relay, such as 68 shown in, Fig. 3, which responds to line current changes for causing the operation of relay 69. This relay 69 impresses on the continuous ring 20 of the receiving distributor RD impulses in accordance with those received from the line conductor extending between the respective stations, and accordingly, when the brush 22 passes over the segments individual to the fourth group, the selecting magnets of the printer individual thereto will be energized in, accordance with the impulses originally transmitted from the I terminal station New York. The printer R will thus function to record the character D. v

Inasmuch as the operation of the mechanism for transmitting between the other stations enumerated is identical to that described in connection with the transmission of a character between New York andSan Francisco through the repeater stations St. Louis and Denver, further detailed description thereof is considered unnecessary.

. It often times is desirable to disconnect the \distributing mechanisms from the respective line sections, thus providing what is commonly referred to as a,direct point repeater. The present invention provides key 79 for disconnecting the respective distributing mechanisms and extending the duplex'set, as shown in Fig. 2 by the dotted lines, in a mannersuch that impulses may be repeated directly from the line 8 to the line 11, or the line 11 to the line 13 directly,

and, of course, vice versa.

Althought the invention "has been disclosed in connection with a particular type of distributing mechanism and a particular combination of repeater stations, and dropotl channels, have been chosen for the purpose of illustration, it is, of course, understood that various departures may be made from the present showing without deviating from the spirit andscope of the invention.

The invention'claimed is: i 1. In atelegraph system, a plurality of terminal stations, a plurality of repeating stations intermediate said terminal stations, continuously operated distributors at each of said stations, means for transmitting a predetermined signal from one of said stations to one of said repeating stations, means at said repeating station for repeating said signal to the adjoining line section and thence to said other repeating and terminal stations, mechanism at each of said stations responsiveto said predetermined signal for indicating directly the amount of line lag, and means at each of said stations for compensating for said line lag in accordance with the indication given by said mechanism.

2. In a telegraph system, a plurality of terminal stations, a plurality of repeating stations intermediate said terminal stations, a synchronous multiplex system connecting the several stations comprising continuously operated distributors, means for sending a predetermined signal from one of said terminal stations to saidlrepeating stations and thence to said other terminal station, indicating mechanism at each of said stations for indicating directly the phase relation of said distributors, printing telegraph mechanism at each of said stations, means for connectin said indicating mechanism with said multiplex system and disconnecting said printing telegraph equipment, and means at each of the stations for adjusting the distributor thereat until it is brought into the desired phase relation with the terminal sta-. tion as determined by said indicating mechanism. 3. In a telegraph system, two remotely situatedtermin'al stations serially connected through a plurality of repeater stations,. each of said stations comprising synchronous multiplex printing telegraph equipment,

means at one of said terminal stations for transmitting phasing impulses to said other terminal station through said repeating stations, means at said repeating stations and said terminal stations responsive to the phasing impulses for indicating directly the amount of line lag, means at each of said stations for compensating for said line lag,

and means at each of said repeating stations .minal stations for thereafter maintaining -said synchronous multiplex equipment in synchronism.

4. In a telegraph system, a plurality of terminal stations, a plurality of repeating stations, one of said terminal stations actin as the correcting station, the other termina station and repeating stations being the'corgag ' rected stations, continuously operated 'distributing mechanismsat each of said stations interconnected by line conductors, means at thecorrecting station for transmitting signaling impulses, and a series of lamps at said other terminal station and each of said repeating stations responsive to signaling impulses for indicating automatically the exact ,phase relation of the corresponding distributing mechanism.

In Witness whereof, I hereunto subscribe my name this 21st day of November A. .D.,

. GEORGE LOCKE, 

